https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99122
--- Comment #16 from Martin Jambor <jamborm at gcc dot gnu.org> --- For the IPA-CP ICE, I am still running some tests, but I am currently leaning towards the following. It might in theory disable IPA-CP in some strange K&R corner cases (I am searching for those with the tests), but I cannot say I care too much even if it does: diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c index 167913cb927..4c8b76c09be 100644 --- a/gcc/ipa-cp.c +++ b/gcc/ipa-cp.c @@ -1186,6 +1186,20 @@ set_single_call_flag (cgraph_node *node, void *) return false; } +/* Return true if the Ith formal parameter in function described by INFO has a + type that is known and safe to accept constants. */ + +static bool +ipa_cp_param_has_safe_type_p (ipa_node_params *info, int i) +{ + tree t = ipa_get_type (info, i); + if (!t) + return false; + /* Attempting to propagate to parameters that are VLAs runs afoul limitations + of how clone materialization implementation. */ + return TREE_CODE (TYPE_SIZE (t)) == INTEGER_CST; +} + /* Initialize ipcp_lattices. */ static void @@ -1277,7 +1291,8 @@ initialize_node_lattices (struct cgraph_node *node) ipcp_param_lattices *plats = ipa_get_parm_lattices (info, i); if (disable || (pre_modified && (surviving_params.length () <= (unsigned) i - || !surviving_params[i]))) + || !surviving_params[i])) + || !ipa_cp_param_has_safe_type_p (info, i)) { plats->itself.set_to_bottom (); plats->ctxlat.set_to_bottom ();